With flat surfaces I could use the table saw to square up
the edges. To do that, first the blade
in the table saw needs to be changed from a rip blade to a crosscut blade. The crosscut blade has different tooth
geometry and a lot more teeth.
The short ends were in good shape but the long dimension
needed a little help. As the piece was
way to long to square using the chop saw, the table saw crosscut fence or my
sled I used an 8’ level clamped to the rip fence and a shim to cut one edge
square to the ends. The shim represents
the amount the piece is out of square along its entire length. To make this work the high point and the shim
has to be in contact with the straight edge the entire length of the cut. Because the rip fence is not long enough, I
add the level as my true full length reference.
The same process is used to square the thin maple glued panels I did
earlier.
Stacking the maple panels and the just completed
cherry/maple sub-assemblies up I could get an idea of what the brick pattern
really would look like.
With the sub-assemblies all nice flat and square I can
cut them up. Each of the 5 panels are
cut into 5 pieces a little over 2” wide.
This will give me my finished chopping block thickness of nearly
2”. I decided leave the 8’ level on as
an extra-long straight edge. With
everything set I made the cuts and stacked them up until I got ready to start
the final assembly process
Now it’s time to cut the maple panels into strips about
2” wide to match the rough thickness of the chopping block. Because the panels are pretty thin and the grain
runs 90 degrees to what you would think they are pretty flimsy so I have to
handle them carefully. I needed to change
the temporary fence on the table saw because there is a small gap under both it
and the table saw rip fence. A different
temporary fence is needed as I don’t want to run the risk of the thin panel
slipping under the fence and messing up my cut.
Last, I set the cut width and start running the panels through making a
stack of bed joint parts. Once cut the
pieces don’t have a lot of strength and need to be supported in a couple of
places as they could easily snap in half.
Here you can see what I mean about the grain direction in a finished
part.
Final assembly of all the pieces can now start. Here is what the first section looks like in
a test clamp. I decided to do the
assembly in stages to keep the number of pieces I had to work with down.
The photo below shows how I have things set up with the
one block done and the next series of pieces ready to be added. On the left are the 2” wide cherry/maple
strips and on the right are the thin maple pieces both ready to have the glue
applied. The center is where I will do
the assembly and clamping. The actual
process is the same as the initial glue-up of the sub-assemblies.
Ever wonder how I get the photos? Well here is the setup for the previous image. To get the right perspective I needed to get far enough back and high enough for the image to make sense. The solution was to stand the camera and tripod on the workbench. I need to use a tripod as the exposures are fairly long in order to give me a good depth-of-field, but that’s a whole different topic.
Anyway, to keep the thin pieces corralled while applying glue I
needed to clamp them in place. However,
since they are only 1/8” thick using traditional clamps would not work out to
well so I used the setup below. The
strips are set on the same piece of plastic wrapped plywood use earlier to glue
them up on then held in place with some thin cutoffs that use tapered wedges
the apply pressure.
Back to glue-up in progress. Here is the glued part which represents half
of the chopping block cleaned up and clamped waiting to cure overnight.
The next day I took off the clamps and then did the same
two stage glue-up over two days to get the second half done and ready for the
next step. Since both of the halves get
glued together, they need to be smooth and the same thickness so its back to
the thickness sander to take out any irregularities and get me close to a
finished surface. I start with 36 grit
in the sander. That may seem a little
extreme but this is end grain cherry and hard maple which is a pretty tough
combination. Once both pieces are
flattened and to the same thickness, I move on to finer sanding grits ending
with 150.
This is the last glue-up, only three pieces. The two halves and the last thin maple strip
between them. Fewer pieces but the joint
alignment is more critical. Before if
things were not quite perfect, I could run them through the thickness sander to
flatten and true up. Not this time as
the piece is too big to fit through the sander so if I am off, I will need to
hand sand the entire high side down to match then flip it over and do it
again. Pretty darn good incentive to get
it right in the first place.
Next up – Final Glue-up, a Defect & Finishing
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